Unable to download any app over cellular network!

Hello everybody, I've been experiencing issues with my Lumia 1520 on denim update. Everytime I want to download an app (ex. WhatsApp or Instagram) it won't let me. It says that is having trouble ATM connecting to the store, I try again later and is the same. I have already hard reset my phone and it didn't work. I am able to download via Wi-Fi and ny network works fine except with this. Is anyone else having the same issue?